I made pizzas last night and they turned out mighty tasty. The only problem is always with the first pie. The crust never gets brown and crispy on the first one. I suspect I don't give the stone adequate time to preheat for fear of running out of heat to cook the last pizza. How long do you suggest I preheat the stone and also how long can I keep a ripping hot fire on a full load of charcoal (I use american royal oak). I have made pizzas more times than I can count and always have the same problem. Thanks.